Communication of direct current (DC) tone location

ABSTRACT

Wireless communications systems and methods related to signaling of direct current (DC) locations of user equipment devices (UEs) in a new radio (NR) network are provided. A wireless communication device receives, from a base station, at least one of a carrier aggregation (CA) configuration or a bandwidth part (BWP) configuration. The wireless communication device determines a direct current (DC) location based on at least one of the CA configuration or the BWP configuration. The wireless communication device transmits, to the base station, a report based on the determined DC location. The wireless communication device communicates, with the base station, a phase tracking reference signal (PTRS) configured based on the report.

CROSS REFERENCE TO RELATED APPLICATIONS

The present application is a continuation of U.S. patent applicationSer. No. 16/378,401, filed Apr. 8, 2019, which claims priority to andthe benefit of the U.S. Provisional Patent Application No. 62/680,225,filed Jun. 4, 2018, U.S. Provisional Patent Application No. 62/660,164,filed Apr. 19, 2018, and U.S. Provisional Patent Application No.62/655,797, filed Apr. 10, 2018, each of which is hereby incorporated byreference in its entirety as if fully set forth below and for allapplicable purposes.

TECHNICAL FIELD

This application relates to wireless communication systems, and moreparticularly to signaling of direct current (DC) locations of userequipment devices (UEs) in a new radio (NR) network. Certain embodimentscan enable and provide solutions and techniques for UEs to efficientlyreport DC locations to improve reference signal (e.g., phase trackingreference signals (PTRSs)) communication.

INTRODUCTION

Wireless communications systems are widely deployed to provide varioustypes of communication content such as voice, video, packet data,messaging, broadcast, and so on. These systems may be capable ofsupporting communication with multiple users by sharing the availablesystem resources (e.g., time, frequency, and power). A wirelessmultiple-access communications system may include a number of basestations (BSs), each simultaneously supporting communications formultiple communication devices, which may be otherwise known as userequipment (UE).

To meet the growing demands for expanded mobile broadband connectivity,wireless communication technologies are advancing from the LTEtechnology to a next generation new radio (NR) technology. For example,NR is designed to provide a lower latency, a higher bandwidth orthroughput, and a higher reliability than LTE. NR is designed to operateover a wide array of spectrum bands, for example, from low-frequencybands below about 1 gigahertz (GHz) and mid-frequency bands from about 1GHz to about 6 GHz, to high-frequency bands such as millimeter wave(mmWave) bands. In addition, NR is designed to operate across differentspectrum types, from licensed spectrum to unlicensed and sharedspectrum.

While the use of higher frequencies (e.g., above 6 GHz) can provide agreater transmission capacity, phase noise levels may increase with thehigher frequencies. Phase noise can impact the performance of certainwireless communication systems. Accordingly, a transmitter may transmita reference signal, such as a phase tracking reference signal (PTRS), tofacilitate phase noise estimations and corrections at a receiver.

Depending on the location of a reference signal within radio frequency(RF) resources, however, a receiver may be unable to efficiently receivethe reference signal due to interference with tones within theresources. For example, a direct current (DC) frequency tone can have alarge, negative impact on the performance of a baseband receiver. The DCfrequency tone can cause high interference and/or high noise for signalprocessing and/or a worse error vector magnitude (EVM) at the receiver.Some receivers may apply DC rejection filtering or puncturing todisregard the tone affected by DC. As such, to enable a receiver toefficiently receive a reference signal, a transmitter may avoidtransmitting a reference signal using frequency resources that overlapwith the DC tone location of the receiver.

In certain wireless communication devices or user equipment devices(UEs), the DC frequency location may be dependent on the receiver'simplementation. For example, in an NR network, a BS may configure a UEfor communications in various bandwidth parts (BWPs) within variouscomponent carriers (CC). Different UEs may have different radiofrequency (RF) receiver implementations. For example, some UEs may use asingle RF and/or baseband chains for all CCs and/or all BWPs, whileother UEs may use different RF and/or baseband chains for different CCsand/or different BWPs. Thus, the DC tone location may vary amongdifferent UEs, as well as within the same UE depending on the RFfrontend configuration in use. Accordingly, a network may determinereference signal configurations according to DC tone locations of UEs.

BRIEF SUMMARY OF SOME EXAMPLES

The following summarizes some aspects of the present disclosure toprovide a basic understanding of the discussed technology. This summaryis not an extensive overview of all contemplated features of thedisclosure, and is intended neither to identify key or critical elementsof all aspects of the disclosure nor to delineate the scope of any orall aspects of the disclosure. Its sole purpose is to present someconcepts of one or more aspects of the disclosure in summary form as aprelude to the more detailed description that is presented later.

Embodiments of the present disclosure provide mechanisms for efficientreporting of direct current (DC) locations. For example, a userequipment (UE) may report DC location information related to the UE'sreceiver and/or the UE's transmitter based on certain events, such as acarrier aggregation (CA) reconfiguration command, a bandwidth part (BWP)switch command, and/or a BWP reconfiguration command received from abase station (BS). The UE may report DC locations per BWP and percomponent carrier (CC). The BS may configure the UE with a set ofreference BWPs for DC location reporting to reduce the amount of DClocation information. The BS may configure the UE with a resourcemapping for UL and/or DL reference signal (e.g., PTRS) communicationsbased on the DC location report. Alternatively, the UE may request theBS to use a certain resource mapping for reference signal (e.g., PTRS)communications based on the UE's transmitter and/or receiver DClocations.

For example, in an aspect of the disclosure, a method of wirelesscommunication is provided that includes receiving, by a wirelesscommunication device from a base station, at least one of a carrieraggregation (CA) configuration or a bandwidth part (BWP) configuration.The method also includes determining, by the wireless communicationdevice, a direct current (DC) location based on at least one of the CAconfiguration or the BWP configuration. The method also includestransmitting, by the wireless communication device to the base station,a report based on the determined DC location.

In an additional aspect of the disclosure, a method of wirelesscommunication is provided that includes transmitting, by a base stationto a wireless communication device, at least one of a carrieraggregation (CA) configuration or a bandwidth part (BWP) configuration.The method also includes receiving, by the base station from thewireless communication device, a report indicating direct current (DC)location information associated with the wireless communication devicein response to at least one of the CA configuration or the BWPconfiguration.

In an additional aspect of the disclosure, an apparatus is provided thatincludes a processor configured to determine a direct current (DC)location based on at least one of a carrier aggregation (CA)configuration or a bandwidth part (BWP) configuration. The apparatusalso includes a transceiver configured to receive, from a base station,the at least one of the CA configuration or the BWP configuration. Thetransceiver is also configured to transmit, to the base station, areport based on the determined DC location.

In an additional aspect of the disclosure, an apparatus is provided thatincludes a transceiver configured to transmit, to a wirelesscommunication device, at least one of a carrier aggregation (CA)configuration or a bandwidth part (BWP) configuration. The transceiveris also configured to receive, from the wireless communication device, areport indicating direct current (DC) location information associatedwith the wireless communication device in response to at least one ofthe CA configuration or the BWP configuration.

In an additional aspect of the disclosure, a computer-readable mediumhaving program code recorded thereon is provided. The program codeincludes code for causing a wireless communication device to receive,from a base station, at least one of a carrier aggregation (CA)configuration or a bandwidth part (BWP) configuration. The program codealso includes code for causing the wireless communication device todetermine a direct current (DC) location based on at least one of the CAconfiguration or the BWP configuration. The program code also includescode for causing the wireless communication device to transmit, to thebase station, a report based on the determined DC location.

In an additional aspect of the disclosure, a computer-readable mediumhaving program code recorded thereon is provided. The program codeincludes code for causing a base station to transmit, to a wirelesscommunication device, at least one of a carrier aggregation (CA)configuration or a bandwidth part (BWP) configuration. The program codealso includes code for causing the base station to receive, from thewireless communication device, a report indicating direct current (DC)location information associated with the wireless communication devicein response to at least one of the CA configuration or the BWPconfiguration.

In an additional aspect of the disclosure, an apparatus is provided thatincludes means for receiving, from a base station, at least one of acarrier aggregation (CA) configuration or a bandwidth part (BWP)configuration. The apparatus also includes means for determining adirect current (DC) location based on at least one of the CAconfiguration or the BWP configuration. The apparatus also includesmeans for transmitting, to the base station, a report based on thedetermined DC location.

In an additional aspect of the disclosure, an apparatus is provided thatincludes means for transmitting, to a wireless communication device, atleast one of a carrier aggregation (CA) configuration or a bandwidthpart (BWP) configuration. The apparatus also includes means forreceiving, from the wireless communication device, a report indicatingdirect current (DC) location information associated with the wirelesscommunication device in response to at least one of the CA configurationor the BWP configuration.

Other aspects, features, and embodiments of the present invention willbecome apparent to those of ordinary skill in the art, upon reviewingthe following description of specific, exemplary embodiments of thepresent invention in conjunction with the accompanying figures. Whilefeatures of the present invention may be discussed relative to certainembodiments and figures below, all embodiments of the present inventioncan include one or more of the advantageous features discussed herein.In other words, while one or more embodiments may be discussed as havingcertain advantageous features, one or more of such features may also beused in accordance with the various embodiments of the inventiondiscussed herein. In similar fashion, while exemplary embodiments may bediscussed below as device, system, or method embodiments it should beunderstood that such exemplary embodiments can be implemented in variousdevices, systems, and methods.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates a wireless communication network according to someembodiments of the present disclosure.

FIG. 2 illustrates an example scenario with user equipment devices (UEs)having different direct current (DC) locations according to someembodiments of the present disclosure.

FIG. 3 illustrates an example bandwidth part (BWP) configurationaccording to some embodiments of the present disclosure.

FIG. 4 illustrates an example BWP configuration according to someembodiments of the present disclosure.

FIG. 5 is a block diagram of an exemplary user equipment (UE) accordingto some embodiments of the present disclosure.

FIG. 6 is a block diagram of an exemplary base station (BS) according tosome embodiments of the present disclosure.

FIG. 7 is a signaling diagram illustrating a DC location reportingmethod according to some embodiments of the present disclosure.

FIG. 8 is a signaling diagram illustrating a DC location reportingmethod according to some embodiments of the present disclosure.

FIG. 9 is a signaling diagram illustrating a DC location reportingmethod according to some embodiments of the present disclosure.

FIG. 10 illustrates a DC location reporting method according to someembodiments of the present disclosure.

FIG. 11 illustrates a DC location report message element according tosome embodiments of the present disclosure.

FIG. 12 illustrates a phase tracking reference signal (PTRS) resourceelement-level (RE-level) offset configuration according to someembodiments of the present disclosure.

FIG. 13 illustrates a DC location report message element according tosome embodiments of the present disclosure.

FIG. 14 is a flow diagram of a DC location reporting and PTRScommunication method according to embodiments of the present disclosure.

FIG. 15 is a flow diagram of a PTRS communication method according tosome embodiments of the present disclosure.

DETAILED DESCRIPTION

The detailed description set forth below, in connection with theappended drawings, is intended as a description of variousconfigurations and is not intended to represent the only configurationsin which the concepts described herein may be practiced. The detaileddescription includes specific details for the purpose of providing athorough understanding of the various concepts. However, it will beapparent to those skilled in the art that these concepts may bepracticed without these specific details. In some instances, well-knownstructures and components are shown in block diagram form in order toavoid obscuring such concepts.

This disclosure relates generally to wireless communications systems,also referred to as wireless communications networks. In variousembodiments, the techniques and apparatus may be used for wirelesscommunication networks such as code division multiple access (CDMA)networks, time division multiple access (TDMA) networks, frequencydivision multiple access (FDMA) networks, orthogonal FDMA (OFDMA)networks, single-carrier FDMA (SC-FDMA) networks, LTE networks, GSMnetworks, 5^(th) Generation (5G) or new radio (NR) networks, as well asother communications networks. As described herein, the terms “networks”and “systems” may be used interchangeably.

An OFDMA network may implement a radio technology such as evolved UTRA(E-UTRA), Institute of Electrical and Electronics Engineers (IEEE)802.11, IEEE 802.16, IEEE 802.20, orthogonal frequency divisionmultiplexing (OFDM) and the like. UTRA, E-UTRA, and Global System forMobile Communications (GSM) are part of universal mobiletelecommunication system (UMTS). In particular, long-term evolution(LTE) is a release of UMTS that uses E-UTRA. UTRA, E-UTRA, GSM, UMTS andLTE are described in documents provided from an organization named “3rdGeneration Partnership Project” (3GPP), and cdma2000® is described indocuments from an organization named “3rd Generation Partnership Project2” (3GPP2). These various radio technologies and standards are known orare being developed. For example, the 3rd Generation Partnership Project(3GPP) is a collaboration between groups of telecommunicationsassociations that aims to define a globally applicable third generation(3G) mobile phone specification. 3GPP long-term evolution LTE is a 3GPPproject which was aimed at improving the universal mobiletelecommunications system (UMTS) mobile phone standard. The 3GPP maydefine specifications for the next generation of mobile networks, mobilesystems, and mobile devices. The present disclosure is concerned withthe evolution of wireless technologies from LTE, 4G, 5G, NR, and beyondwith shared access to wireless spectrum between networks using acollection of new and different radio access technologies or radio airinterfaces.

In particular, 5G networks contemplate diverse deployments, diversespectrum, and diverse services and devices that may be implemented usingan OFDM-based unified, air interface. In order to achieve these goals,further enhancements to LTE and LTE-A are considered in addition todevelopment of the new radio technology for 5G NR networks. The 5G NRwill be capable of scaling to provide coverage (1) to a massive Internetof things (IoTs) with an ultra-high density (e.g., ˜1M nodes/km²),ultra-low complexity (e.g., ˜10 s of bits/sec), ultra-low energy (e.g.,˜10+ years of battery life), and deep coverage with the capability toreach challenging locations; (2) including mission-critical control withstrong security to safeguard sensitive personal, financial, orclassified information, ultra-high reliability (e.g., ˜99.9999%reliability), ultra-low latency (e.g., ˜1 ms), and users with wideranges of mobility or lack thereof; and (3) with enhanced mobilebroadband including extreme high capacity (e.g., ˜10 Tbps/km²), extremedata rates (e.g., multi-Gbps rate, 100+ Mbps user experienced rates),and deep awareness with advanced discovery and optimizations.

The 5G NR may be implemented to use optimized OFDM-based waveforms withscalable numerology and transmission time period (TTI); having a common,flexible framework to efficiently multiplex services and features with adynamic, low-latency time division duplex (TDD)/frequency divisionduplex (FDD) design; and with advanced wireless technologies, such asmassive multiple input, multiple output (MIMO), robust millimeter wave(mmWave) transmissions, advanced channel coding, and device-centricmobility. Scalability of the numerology in 5G NR, with scaling ofsubcarrier spacing, may efficiently address operating diverse servicesacross diverse spectrum and diverse deployments. For example, in variousoutdoor and macro coverage deployments of less than 3 GHz FDD/TDDimplementations, subcarrier spacing may occur with 15 kHz, for exampleover 1, 5, 10, 20 MHz, and the like BW. For other various outdoor andsmall cell coverage deployments of TDD greater than 3 GHz, subcarrierspacing may occur with 30 kHz over 80/100 MHz BW. For other variousindoor wideband implementations, using a TDD over the unlicensed portionof the 5 GHz band, the subcarrier spacing may occur with 60 kHz over a160 MHz BW. Finally, for various deployments transmitting with mmWavecomponents at a TDD of 28 GHz, subcarrier spacing may occur with 120 kHzover a 500 MHz BW.

The scalable numerology of the 5G NR facilitates scalable TTI fordiverse latency and quality of service (QoS) requirements. For example,shorter TTI may be used for low latency and high reliability, whilelonger TTI may be used for higher spectral efficiency. The efficientmultiplexing of long and short TTIs to allow transmissions to start onsymbol boundaries. 5G NR also contemplates a self-contained integratedsubframe design with uplink/downlink scheduling information, data, andacknowledgement in the same subframe. The self-contained integratedsubframe supports communications in unlicensed or contention-basedshared spectrum, adaptive uplink/downlink that may be flexiblyconfigured on a per-cell basis to dynamically switch between uplink anddownlink to meet the current traffic needs.

Various other aspects and features of the disclosure are furtherdescribed below. It should be apparent that the teachings herein may beembodied in a wide variety of forms and that any specific structure,function, or both being disclosed herein is merely representative andnot limiting. Based on the teachings herein one of an ordinary level ofskill in the art should appreciate that an aspect disclosed herein maybe implemented independently of any other aspects and that two or moreof these aspects may be combined in various ways. For example, anapparatus may be implemented or a method may be practiced using anynumber of the aspects set forth herein. In addition, such an apparatusmay be implemented or such a method may be practiced using otherstructure, functionality, or structure and functionality in addition toor other than one or more of the aspects set forth herein. For example,a method may be implemented as part of a system, device, apparatus,and/or as instructions stored on a computer readable medium forexecution on a processor or computer. Furthermore, an aspect maycomprise at least one element of a claim.

NR may provide phase tracking reference signals (PTRSs) to facilitatephase tracking at UEs and BSs. For example, a BS may include a PTRS in aDL signal to enable a UE to track and correct the phase error in thereceived DL signal. Similarly, a UE may include a PTRS in a UL signal toenable a BS to track and correct the phase error in the received ULsignal. In some instances, PTRSs may be present in a DL signal and/or aUL signal frequently. For example, a network may configure a PTRStransmission in a DL signal or a UL signal at every symbol using onesubcarrier.

As described above, a DC frequency tone can cause high noise at the DClocation. To avoid having a PTRS being filtered out due to DC rejectionfiltering or being interfered by a DC tone, a network may schedule PTRStransmissions on frequencies different from a frequency or frequenciesthat correspond to a DC tone of a UE. In other words, the network mayconfigure resources for PTRS transmissions based on the DC tonelocations of a UE's transmitter and receiver. However, as describedabove, different UEs may have different DC tone locations depending onthe RF configurations, which may be based on a CC configuration and/or aBWP configuration of a UE. While a UE can report DC locations used ofthe UE's transmitter and receiver to the BS, the signaling may becomplex. For example, the number of potential DC locations can be largewhen taking into account of BWPs and CC, where a radio access network(RAN) may configure up to about eight CCs in a particular frequency bandand up to about four configured BWPs in each CC. Thus, a UE may berequired to signal up to about 4⁸ combinations of DC locations to thenetwork. Assuming each DC location requires a 12-bit information elementfield (as the value range is 0 to 3299), then the 4⁸ DC locationsreporting may require at least a UL signaling space of about 800kilobits. Further, a UE may be required to process a received radioresource control (RRC) message (e.g., including CA/CC/BWP configurationcommands) and send back a response message within about 15 milliseconds(ms) for the worst case. The computational power required for theidentification of the DC locations for all the possible combinations maybe large, and thus may be difficult to satisfy the RRC processing timerequirement.

The present application describes mechanisms for a UE to efficientlysignal DC location information to a BS. The reporting of DC locationinformation may be triggered by events, such as a carrier aggregation(CA) reconfiguration command, a bandwidth part (BWP) switch command,and/or a BWP reconfiguration command received from the BS. The UE maydetermine the DC location by considering a CA configuration and/or BWPconfigurations. To reduce the amount of information bits required forthe signaling, the BS may provide the UE with a set of reference BWPsfor DC location reporting. The UE may determine DC locations for the setof reference BWPs and report corresponding DC locations for thereference BWPs. The DC locations may include one or more DC locations ofthe UE's transmitter (e.g., for UL transmission) and one or more DClocations of the UE's receiver (e.g., for downlink reception).

In an embodiment, the UE may include a band report including DClocations as a function of configured bands or BWPs. In an embodiment,the UE may report a subcarrier offset of a subcarrier within a resourceblock (RB) overlapping with the DC location and/or the location of theRB. In an embodiment, the UE may select a PTRS-resource element(RE)-offset parameter for a determined DC location and report thePTRS-RE-offset parameter to the BS. The BS may configure PTRSs accordingto the reported subcarrier offset, the reported RB, and/or the reportedPTRS-RE-offset parameter.

FIG. 1 illustrates a wireless communication network 100 according tosome embodiments of the present disclosure. The network 100 may be a 5Gnetwork. The network 100 includes a number of base stations (BSs) 105and other network entities. ABS 105 may be a station that communicateswith UEs 115 and may also be referred to as an evolved node B (eNB), anext generation eNB (gNB), an access point, and the like. Each BS 105may provide communication coverage for a particular geographic area. In3GPP, the term “cell” can refer to this particular geographic coveragearea of a BS 105 and/or a BS subsystem serving the coverage area,depending on the context in which the term is used.

ABS 105 may provide communication coverage for a macro cell or a smallcell, such as a pico cell or a femto cell, and/or other types of cell. Amacro cell generally covers a relatively large geographic area (e.g.,several kilometers in radius) and may allow unrestricted access by UEswith service subscriptions with the network provider. A small cell, suchas a pico cell, would generally cover a relatively smaller geographicarea and may allow unrestricted access by UEs with service subscriptionswith the network provider. A small cell, such as a femto cell, wouldalso generally cover a relatively small geographic area (e.g., a home)and, in addition to unrestricted access, may also provide restrictedaccess by UEs having an association with the femto cell (e.g., UEs in aclosed subscriber group (CSG), UEs for users in the home, and the like).ABS for a macro cell may be referred to as a macro BS. ABS for a smallcell may be referred to as a small cell BS, a pico BS, a femto BS or ahome BS. In the example shown in FIG. 1 , the BSs 105 d and 105 e may beregular macro BSs, while the BSs 105 a-105 c may be macro BSs enabledwith one of three dimension (3D), full dimension (FD), or massive MIMO.The BSs 105 a-105 c may take advantage of their higher dimension MIMOcapabilities to exploit 3D beamforming in both elevation and azimuthbeamforming to increase coverage and capacity. The BS 105 f may be asmall cell BS which may be a home node or portable access point. A BS105 may support one or multiple (e.g., two, three, four, and the like)cells.

The network 100 may support synchronous or asynchronous operation. Forsynchronous operation, the BSs may have similar frame timing, andtransmissions from different BSs may be approximately aligned in time.For asynchronous operation, the BSs may have different frame timing, andtransmissions from different BSs may not be aligned in time.

The UEs 115 are dispersed throughout the wireless network 100, and eachUE 115 may be stationary or mobile. A UE 115 may also be referred to asa terminal, a mobile station, a subscriber unit, a station, or the like.A UE 115 may be a cellular phone, a personal digital assistant (PDA), awireless modem, a wireless communication device, a handheld device, atablet computer, a laptop computer, a cordless phone, a wireless localloop (WLL) station, or the like. In one aspect, a UE 115 may be a devicethat includes a Universal Integrated Circuit Card (UICC). In anotheraspect, a UE may be a device that does not include a UICC. In someaspects, the UEs 115 that do not include UICCs may also be referred toas IoT devices or internet of everything (IoE) devices. The UEs 115a-115 d are examples of mobile smart phone-type devices accessingnetwork 100 A UE 115 may also be a machine specifically configured forconnected communication, including machine type communication (MTC),enhanced MTC (eMTC), narrowband IoT (NB-IoT) and the like. The UEs 115e-115 k are examples of various machines configured for communicationthat access the network 100. A UE 115 may be able to communicate withany type of the BSs, whether macro BS, small cell, or the like. In FIG.1 , a lightning bolt (e.g., communication links) indicates wirelesstransmissions between a UE 115 and a serving BS 105, which is a BSdesignated to serve the UE 115 on the downlink and/or uplink, or desiredtransmission between BSs, and backhaul transmissions between BSs.

In operation, the BSs 105 a-105 c may serve the UEs 115 a and 115 busing 3D beamforming and coordinated spatial techniques, such ascoordinated multipoint (CoMP) or multi-connectivity. The macro BS 105 dmay perform backhaul communications with the BSs 105 a-105 c, as well assmall cell, the BS 105 f. The macro BS 105 d may also transmitsmulticast services which are subscribed to and received by the UEs 115 cand 115 d. Such multicast services may include mobile television orstream video, or may include other services for providing communityinformation, such as weather emergencies or alerts, such as Amber alertsor gray alerts.

The network 100 may also support mission critical communications withultra-reliable and redundant links for mission critical devices, such asthe UE 115 e, which may be a drone. Redundant communication links withthe UE 115 e may include links from the macro BSs 105 d and 105 e, aswell as links from the small cell BS 105 f. Other machine type devices,such as the UE 115 f (e.g., a thermometer), the UE 115 g (e.g., smartmeter), and UE 115 h (e.g., wearable device) may communicate through thenetwork 100 either directly with BSs, such as the small cell BS 105 f,and the macro BS 105 e, or in multi-hop configurations by communicatingwith another user device which relays its information to the network,such as the UE 115 f communicating temperature measurement informationto the smart meter, the UE 115 g, which is then reported to the networkthrough the small cell BS 105 f. The network 100 may also provideadditional network efficiency through dynamic, low-latency TDD/FDDcommunications, such as in a vehicle-to-vehicle (V2V)

In some implementations, the network 100 utilizes OFDM-based waveformsfor communications. An OFDM-based system may partition the system BWinto multiple (K) orthogonal subcarriers, which are also commonlyreferred to as subcarriers, tones, bins, or the like. Each subcarriermay be modulated with data. In some instances, the subcarrier spacingbetween adjacent subcarriers may be fixed, and the total number ofsubcarriers (K) may be dependent on the system BW. The system BW mayalso be partitioned into subbands. In other instances, the subcarrierspacing and/or the duration of TTIs may be scalable.

In an embodiment, the BSs 105 can assign or schedule transmissionresources (e.g., in the form of time-frequency resource blocks (RB)) fordownlink (DL) and uplink (UL) transmissions in the network 100. DLrefers to the transmission direction from a BS 105 to a UE 115, whereasUL refers to the transmission direction from a UE 115 to a BS 105. Thecommunication can be in the form of radio frames. A radio frame may bedivided into a plurality of subframes, for example, about 10. Eachsubframe can be divided into slots, for example, about 2. Each slot maybe further divided into mini-slots. In a FDD mode, simultaneous UL andDL transmissions may occur in different frequency bands. For example,each subframe includes a UL subframe in a UL frequency band and a DLsubframe in a DL frequency band. In a time-division duplexing (TDD)mode, UL and DL transmissions occur at different time periods using thesame frequency band. For example, a subset of the subframes (e.g., DLsubframes) in a radio frame may be used for DL transmissions and anothersubset of the subframes (e.g., UL subframes) in the radio frame may beused for UL transmissions.

The DL subframes and the UL subframes can be further divided intoseveral regions. For example, each DL or UL subframe may havepre-defined regions for transmissions of reference signals, controlinformation, and data. Reference signals are predetermined signals thatfacilitate the communications between the BSs 105 and the UEs 115. Forexample, a reference signal can have a particular pilot pattern orstructure, where pilot tones may span across an operational BW orfrequency band, each positioned at a pre-defined time and a pre-definedfrequency. For example, a BS 105 may transmit cell specific referencesignals (CRSs) and/or channel state information-reference signals(CSI-RSs) to enable a UE 115 to estimate a DL channel. Similarly, a UE115 may transmit sounding reference signals (SRSs) to enable a BS 105 toestimate a UL channel. Control information may include resourceassignments and protocol controls. Data may include protocol data and/oroperational data. In some embodiments, the BSs 105 and the UEs 115 maycommunicate using self-contained subframes. A self-contained subframemay include a portion for DL communication and a portion for ULcommunication. A self-contained subframe can be DL-centric orUL-centric. A DL-centric subframe may include a longer duration for DLcommunication than for UL communication. A UL-centric subframe mayinclude a longer duration for UL communication than for ULcommunication.

In an embodiment, the network 100 may be an NR network deployed over alicensed spectrum. The BSs 105 can transmit synchronization signals(e.g., including a primary synchronization signal (PSS) and a secondarysynchronization signal (SSS)) in the network 100 to facilitatesynchronization. The BSs 105 can broadcast system information associatedwith the network 100 (e.g., including a master information block (MIB),remaining minimum system information (RMSI), and other systeminformation (OSI)) to facilitate initial network access. In someinstances, the BSs 105 may broadcast the PSS, the SSS, and/or the MIB inthe form of synchronization signal blocks (SSBs) over a physicalbroadcast channel (PBCH) and may broadcast the RMSI and/or the OSI overa physical downlink shared channel (PDSCH).

In an embodiment, a UE 115 attempting to access the network 100 mayperform an initial cell search by detecting a PSS from a BS 105. The PSSmay enable synchronization of period timing and may indicate a physicallayer identity value. The UE 115 may then receive a SSS. The SSS mayenable radio frame synchronization, and may provide a cell identityvalue, which may be combined with the physical layer identity value toidentify the cell. The SSS may also enable detection of a duplexing modeand a cyclic prefix length. Some systems, such as TDD systems, maytransmit an SSS but not a PSS. Both the PSS and the SSS may be locatedin a central portion of a carrier, respectively.

After receiving the PSS and SSS, the UE 115 may receive a MIB. The MIBmay include system information for initial network access and schedulinginformation for RMSI and/or OSI. After decoding the MIB, the UE 115 mayreceive RMSI and/or OSI. The RMSI and/or OSI may include radio resourceconfiguration (RRC) information related to random access channel (RACH)procedures, paging, control resource set (CORESET) for physical downlinkcontrol channel (PDCCH) monitoring, physical uplink control channel(PUCCH), physical uplink shared channel (PUSCH), power control, SRS, andcell barring. After obtaining the MIB, the RMSI and/or the OSI, the UE115 can perform a random access procedure to establish a connection withthe BS 105. After establishing a connection, the UE 115 and the BS 105can enter a normal operation stage, where operational data may beexchanged.

In some embodiments, the network 100 may be an NR network. The DC tonelocations at different UEs 115 may be different. In some embodiments,the UEs 115 may configure different DC tones for different componentcarrier (CC) configurations. In some embodiments, the UEs 115 mayconfigure different DC tones for different bandwidth part (BWP)configurations. At the radio frontend (RF) receiver of a UE 115, theremay be peak signal at the DC location. The peak signal is a source ofnoise for signal processing at the receiver. Thus, the basebandprocessing of the UE may filter out some frequencies near by the DCtone. In an embodiment, the BSs 105 may transmit phase trackingreference signals (PTRSs) to facilitate phase tracking at the UEs 115.To avoid collisions between the PTRSs and the DC tone locations of theUEs 115, the UEs 115 may report corresponding DC tone locations to theBSs 105 and the BSs may configure PTRSs based on the DC tone locationreports. U.S. patent application Ser. No. 15/707,821 and U.S.Publication No. 2018/0091350 describe enhancements to PTRS design andscrambling, each of which is hereby incorporated by reference in itsentirety and for all applicable purposes. Mechanisms for DC tonelocation reporting and PTRS configurations are described in greaterdetail herein.

FIG. 2 illustrates an example scenario 200 with UEs having different DClocations according to some embodiments of the present disclosure. TheUEs may correspond to the UEs 115 of the network 100. In FIG. 2 , they-axis represents frequency in some constant units. For example, anetwork may be configured with two CCs 210 and 220. A UE A and a UE B ofthe network may have different DC locations. For example, UE A may useone RF and/or baseband chain for communicating over the CC 210 andanother RF and/or baseband chain for communicating over the CC 220.Conversely, UE B may use the same RF and/or baseband chain forcommunicating over the CC 210 and the CC 220. As shown, UE A isconfigured with a DC location 202 for the CC 210 and a different DClocation 206 for the CC 220, while UE B is configured with a DC location204 for both the CC 210 and the CC 220. The DC locations 202 and 206 maybe DC locations of the UE A's transmitter and/or the UE A's receiver.Similarly, the DC location 204 may be a DC location of the UE B'stransmitter and/or the UE B's receiver.

In an embodiment, a UE may determine the DC location based on a currentRF configuration. The current RF configuration may be dependent on acarried aggregation (CA) configuration and/or an active BWPconfiguration. In some embodiments, the transmitter and the receiver ofa UE may have different DC locations. In some other embodiments, thetransmitter and the receiver of a UE may have the same DC locations.

In an embodiment, the DC location of a UE is dependent on theimplementation of the UE. As such, each UE in a network can have adifferent DC location. For example, one UE (chipset) may choose thecenter frequency of a CC as the DC location, another UE (chipset) maychoose the center frequency of contiguous CCs, or yet another UE(chipset) may choose the center frequency of all configured CCsregardless of whether the CCs are contiguous or non-contiguous.

In an embodiment, a UE may determine the DC location further based on aconfigured BWP. Each BWP may have a different center frequency and a UEmay change the DC location upon a BWP switch command to anotherconfigured BWP. Thus, a UE may have different DC locations for differentBWPs.

FIG. 3 illustrates an example BWP configuration 300 according to someembodiments of the present disclosure. The configuration 300 may beemployed by the network 100 for BWP configurations. For example, a BSsuch as the BSs 105 may configure up to about four BWPs for each CC(e.g., the CCs 210 and 220) and may configure a UE such as the UEs 115with one of the BWP as an active BWP for data communications. In FIG. 3, the y-axis represents frequency in some constant units. Theconfiguration 300 includes a BWP 310 and a BWP 320. The BWPs 310 and 320have the same center frequency 302. In an embodiment, when a UE isconfigured with the BWP 310 and 320, the UE may configure the same DClocation for both BWPs 310 and 320. In other words, the UE may notchange the DC location when switching between the BWPs 310 and 320.

FIG. 4 illustrates an example BWP configuration 400 according to someembodiments of the procedure. The configuration 400 may be employed bythe network 100. In FIG. 4 , the y-axis represents frequency in someconstant units. Similar to the configuration 300, a BS such as the BSs105 may configure up to about four BWPs for each CC (e.g., the CCs 210and 220) and may configure a UE such as the UEs 115 with one of the BWPas an active BWP for data communications. However, the BS may configureBWPs with different center frequencies. As shown, the configuration 400includes a BWP 410 and a BWP 420. The BWP 410 includes a centerfrequency 402. The BWP 420 includes a center frequency 404 differentfrom the center frequency 402. In an embodiment, a UE may applydifferent DC locations for the BWPs 410 and 420. In other words, the UEmay change the DC location when switching between the BWPs 410 and 420.

FIG. 5 is a block diagram of an exemplary UE 500 according toembodiments of the present disclosure. The UE 500 may be a UE 115 or aUE 215 as discussed above. As shown, the UE 500 may include a processor502, a memory 504, a DC location reporting module 508, a transceiver 510including a modem subsystem 512 and a radio frequency (RF) unit 514, andone or more antennas 516. These elements may be in direct or indirectcommunication with each other, for example via one or more buses.

The processor 502 may include a central processing unit (CPU), a digitalsignal processor (DSP), an application specific integrated circuit(ASIC), a controller, a field programmable gate array (FPGA) device,another hardware device, a firmware device, or any combination thereofconfigured to perform the operations described herein. The processor 502may also be implemented as a combination of computing devices, e.g., acombination of a DSP and a microprocessor, a plurality ofmicroprocessors, one or more microprocessors in conjunction with a DSPcore, or any other such configuration.

The memory 504 may include a cache memory (e.g., a cache memory of theprocessor 502), random access memory (RAM), magnetoresistive RAM (MRAM),read-only memory (ROM), programmable read-only memory (PROM), erasableprogrammable read only memory (EPROM), electrically erasableprogrammable read only memory (EEPROM), flash memory, solid state memorydevice, hard disk drives, other forms of volatile and non-volatilememory, or a combination of different types of memory. In an embodiment,the memory 504 includes a non-transitory computer-readable medium. Thememory 504 may store instructions 506. The instructions 506 may includeinstructions that, when executed by the processor 502, cause theprocessor 502 to perform the operations described herein with referenceto the UEs 115 in connection with embodiments of the present disclosure,for example, aspects of FIGS. 7-14 . Instructions 506 may also bereferred to as code. The terms “instructions” and “code” should beinterpreted broadly to include any type of computer-readablestatement(s). For example, the terms “instructions” and “code” may referto one or more programs, routines, sub-routines, functions, procedures,etc. “Instructions” and “code” may include a single computer-readablestatement or many computer-readable statements.

The DC location reporting module 508 may be implemented via hardware,software, or combinations thereof. For example, the DC locationreporting module 508 may be implemented as a processor, circuit, and/orinstructions 506 stored in the memory 504 and executed by the processor502. In some examples, the DC location reporting module 508 can beintegrated within the modem subsystem 512. For example, the DC locationreporting module 508 can be implemented by a combination of softwarecomponents (e.g., executed by a DSP or a general processor) and hardwarecomponents (e.g., logic gates and circuitry) within the modem subsystem512.

The DC location reporting module 508 may be used for various aspects ofthe present disclosure, for example, aspects of FIGS. 7-14 . Forexample, the DC location reporting module 508 is configured to receive aCA configuration/reconfiguration command, a CCconfiguration/reconfiguration command, and/or a BWP configuration/switchcommand from a BS such as the BSs 105, determine DC locations based onthe received commands and/or the RF implementations of the UE 500,select a UL PTRS configuration and/or a DL PTRS configuration based onthe determined DC locations, report DC location information and/or PTRSconfiguration selections to the BS, receive UL and/or DL PTRSconfigurations from the BS, and/or include PTRSs in UL transmissionsbased on the received UL and/or DL PTRS configurations, as described ingreater detail herein.

As shown, the transceiver 510 may include the modem subsystem 512 andthe RF unit 514. The transceiver 510 can be configured to communicatebi-directionally with other devices, such as the BSs 105. The modemsubsystem 512 may be configured to modulate and/or encode the data fromthe memory 504, and/or the DC location reporting module 508 according toa modulation and coding scheme (MCS), e.g., a low-density parity check(LDPC) coding scheme, a turbo coding scheme, a convolutional codingscheme, a digital beamforming scheme, etc. The RF unit 514 may beconfigured to process (e.g., perform analog to digital conversion ordigital to analog conversion, etc.) modulated/encoded data from themodem subsystem 512 (on outbound transmissions) or of transmissionsoriginating from another source such as a UE 115 or a BS 105. The RFunit 514 may be further configured to perform analog beamforming inconjunction with the digital beamforming. Although shown as integratedtogether in transceiver 510, the modem subsystem 512 and the RF unit 514may be separate devices that are coupled together at the UE 115 toenable the UE 115 to communicate with other devices.

The RF unit 514 may provide the modulated and/or processed data, e.g.data packets (or, more generally, data messages that may contain one ormore data packets and other information), to the antennas 516 fortransmission to one or more other devices. The antennas 516 may furtherreceive data messages transmitted from other devices. The antennas 516may provide the received data messages for processing and/ordemodulation at the transceiver 510. The antennas 516 may includemultiple antennas of similar or different designs in order to sustainmultiple transmission links. The RF unit 514 may configure the antennas516.

In some embodiments, the UE 500 may include multiple modem subsystems512 and/or multiple RF units 514. The modem subsystems 512 may performprocessing at a baseband. Thus, the modem subsystems 512 may be referredto as baseband transmitters and/or baseband receivers. In the transmitpath, the RF units 514 may include an RF up-converter that up-convertsUL baseband signals generated by the modem subsystems 512 tocorresponding RF carrier frequencies for transmissions over the antennas516. In the receive path, the RF units 514 may include an RFdown-converter that down-converts DL RF signals received from theantennas 516 to a baseband for processing by the modem subsystems 512.In some embodiments, the modem subsystems 512 and/or the RF units 514may be configured based on BWP configurations and/or CA configurationsreceived from the BS. In some embodiments, the same modem subsystem 512and the same RF unit 514 can be used for all BWP configuration and allCA configurations.

FIG. 6 is a block diagram of an exemplary BS 600 according toembodiments of the present disclosure. The BS 600 may be a BS 105 asdiscussed above. As shown, the BS 600 may include a processor 602, amemory 604, a PTRS configuration module 608, a transceiver 610 includinga modem subsystem 612 and a RF unit 614, and one or more antennas 616.These elements may be in direct or indirect communication with eachother, for example via one or more buses.

The processor 602 may have various features as a specific-typeprocessor. For example, these may include a CPU, a DSP, an ASIC, acontroller, a FPGA device, another hardware device, a firmware device,or any combination thereof configured to perform the operationsdescribed herein. The processor 602 may also be implemented as acombination of computing devices, e.g., a combination of a DSP and amicroprocessor, a plurality of microprocessors, one or moremicroprocessors in conjunction with a DSP core, or any other suchconfiguration.

The memory 604 may include a cache memory (e.g., a cache memory of theprocessor 602), RAM, MRAM, ROM, PROM, EPROM, EEPROM, flash memory, asolid state memory device, one or more hard disk drives, memristor-basedarrays, other forms of volatile and non-volatile memory, or acombination of different types of memory. In some embodiments, thememory 604 may include a non-transitory computer-readable medium. Thememory 604 may store instructions 606. The instructions 606 may includeinstructions that, when executed by the processor 602, cause theprocessor 602 to perform operations described herein, for example,aspects of FIGS. 7-13 and 15 . Instructions 606 may also be referred toas code, which may be interpreted broadly to include any type ofcomputer-readable statement(s) as discussed above with respect to FIG. 5.

The PTRS configuration module 608 may be implemented via hardware,software, or combinations thereof. For example, the PTRS configurationmodule 608 may be implemented as a processor, circuit, and/orinstructions 606 stored in the memory 604 and executed by the processor602. In some examples, the PTRS configuration module 608 can beintegrated within the modem subsystem 612. For example, the PTRSconfiguration module 608 can be implemented by a combination of softwarecomponents (e.g., executed by a DSP or a general processor) and hardwarecomponents (e.g., logic gates and circuitry) within the modem subsystem612.

The PTRS configuration module 608 may be used for various aspects of thepresent disclosure, for example, aspects of FIGS. 7-13 and 15 . Forexample, the PTRS configuration module 608 is configured to determine CAconfiguration/reconfiguration, CC configuration/reconfiguration, and/orBWP configuration/switch for a UE such as the UEs 115 and 500, receiveDC location reports and/or PTRS configuration selections from the UE,configure PTRSs for the UE avoiding the DC locations indicated in thereports or based on the PTRS configuration selections to facilitatephase tracking at the UE, and/or include PTRSs in DL signaltransmissions, as described in greater detail herein.

As shown, the transceiver 610 may include the modem subsystem 612 andthe RF unit 614. The transceiver 610 can be configured to communicatebi-directionally with other devices, such as the UEs 115 and/or anothercore network element. The modem subsystem 612 may be configured tomodulate and/or encode data according to a MCS, e.g., a LDPC codingscheme, a turbo coding scheme, a convolutional coding scheme, a digitalbeamforming scheme, etc. The RF unit 614 may be configured to process(e.g., perform analog to digital conversion or digital to analogconversion, etc.) modulated/encoded data from the modem subsystem 612(on outbound transmissions) or of transmissions originating from anothersource such as a UE 115 or 500. The RF unit 614 may be furtherconfigured to perform analog beamforming in conjunction with the digitalbeamforming. Although shown as integrated together in transceiver 610,the modem subsystem 612 and the RF unit 614 may be separate devices thatare coupled together at the BS 105 to enable the BS 105 to communicatewith other devices.

The RF unit 614 may provide the modulated and/or processed data, e.g.data packets (or, more generally, data messages that may contain one ormore data packets and other information), to the antennas 616 fortransmission to one or more other devices. This may include, forexample, transmission of information to complete attachment to a networkand communication with a camped UE 115 or 500 according to embodimentsof the present disclosure. The antennas 616 may further receive datamessages transmitted from other devices and provide the received datamessages for processing and/or demodulation at the transceiver 610. Theantennas 616 may include multiple antennas of similar or differentdesigns in order to sustain multiple transmission links.

FIGS. 7-9 illustrate various mechanisms for reporting DC locations basedon events triggered by a CA reconfiguration, a BWP switch, and/or a BWPreconfiguration.

FIG. 7 is a signaling diagram illustrating a DC location reportingmethod 700 according to some embodiments of the procedure. The method700 is employed by the network 100. Steps of the method 700 can beexecuted by computing devices (e.g., a processor, processing circuit,and/or other suitable component) of wireless communication devices, suchas the BSs 105 and 600 and the UEs 115 and 500. As illustrated, themethod 700 includes a number of enumerated steps, but embodiments of themethod 700 may include additional steps before, after, and in betweenthe enumerated steps. In some embodiments, one or more of the enumeratedsteps may be omitted or performed in a different order. The method 700illustrates one BS and one UE for purposes of simplicity of discussion,though it will be recognized that embodiments of the present disclosuremay scale to many more UEs and/or BSs. The method 700 illustrates a DCreporting based on CA reconfiguration.

At step 710, the BS transmits a CA reconfiguration command to the UE.The CA reconfiguration may include a removal of a CC (e.g., the CCs 210and 210) and/or an addition of a CC to a previous CA configuration.

At step 720, upon receiving the CA reconfiguration command, the UE maydetermine a DC location based on the reconfigured CA configuration. Insome embodiments, the UE may determine a DC location of the UE'stransmitter and a DC location of the UE's receiver.

At step 730, the UE may transmit a DC location report to the BS. The DClocation report may indicate the DC locations determined for thereconfigured CA configuration.

At step 740, the BS determines PTRS configurations based on the DClocation report. For example, the BS may configure UL and/or DLresources for PTRS transmissions avoiding DC tones indicated in thereceived DC location report.

At step 750, the BS transmits PTRS configurations to the UE.

At step 760, the BS transmits PTRSs using the configured DL resources tofacilitate phase tracking at the UE. For example, the PTRSs are includedin DL signals carrying DL data.

At step 770, the UE transmits PTRSs using the configured UL resources tofacilitate phase tracking at the BS. For example, the PTRSs are includedin UL signals carrying UL data.

The triggering of DC location reports based on CA reconfigurations maybe suitable when all configured BWPs have the same center frequency(e.g., as shown in the configuration 300) or when there is only one BWPwithin a carrier.

FIG. 8 is a signaling diagram illustrating a DC location reportingmethod 800 according to some embodiments of the procedure. The method800 is employed by the network 100. Steps of the method 800 can beexecuted by computing devices (e.g., a processor, processing circuit,and/or other suitable component) of wireless communication devices, suchas the BSs 105 and 600 and the UEs 115 and 500. As illustrated, themethod 800 includes a number of enumerated steps, but embodiments of themethod 800 may include additional steps before, after, and in betweenthe enumerated steps. In some embodiments, one or more of the enumeratedsteps may be omitted or performed in a different order. The method 800illustrates one BS and one UE for purposes of simplicity of discussion,though it will be recognized that embodiments of the present disclosuremay scale to many more UEs and/or BSs. The method 800 illustrates a DCreporting based on a BWP switch.

At step 810, the BS transmits a BWP switch command to the UE. Forexample, the BWP switch command may switch one or more active BWPs(e.g., the BWPs 310, 320, 410, and 420) of the UE to other BWPs. In anembodiment, the BS may switch an active BWP of the UE using an RRCreconfiguration procedure.

At step 820, upon receiving the BWP switch command, the UE may determinea DC location based on an active BWP indicated by the BWP switchcommand. In some embodiments, the UE may determine a DC location of theUE's transmitter and a DC location of the UE's receiver

At step 830, the UE may transmit a DC location report to the BS. The DClocation report may indicate the DC location determined for the switchedBWP.

At step 840, the BS determines PTRS configurations based on the DClocation report. For example, the BS may configure UL and/or DLresources for PTRS transmissions avoiding DC tones indicated in thereceived DC location report.

At step 850, the BS transmits PTRS configurations to the UE.

At step 860, the BS transmits PTRSs using the configured DL resources tofacilitate phase tracking at the UE. For example, the PTRSs are includedin DL signals carrying DL data.

At step 870, the UE transmits PTRSs using the configured UL resources tofacilitate phase tracking at the BS. For example, the PTRSs are includedin UL signals carrying UL data.

FIG. 9 is a signaling diagram illustrating a DC location reportingmethod 900 according to some embodiments of the present disclosure. Themethod 900 is employed by the network 100. Steps of the method 900 canbe executed by computing devices (e.g., a processor, processing circuit,and/or other suitable component) of wireless communication devices, suchas the BSs 105 and 600 and the UEs 115 and 500. As illustrated, themethod 900 includes a number of enumerated steps, but embodiments of themethod 900 may include additional steps before, after, and in betweenthe enumerated steps. In some embodiments, one or more of the enumeratedsteps may be omitted or performed in a different order. The method 900illustrates one BS and one UE for purposes of simplicity of discussion,though it will be recognized that embodiments of the present disclosuremay scale to many more UEs and/or BSs. The method 900 illustrates a DCreporting based on a BWP reconfiguration with CA configurationconsideration.

At step 910, the BS transmits a BWP reconfiguration command to the UE.The BWP reconfiguration may include a removal of a BWP (e.g., the BWPs310, 320, 410, and 420) and/or an addition of a BWP to a previous BWPconfiguration.

At step 920, upon receiving the BWP reconfiguration command, the UE maydetermine a DC location based on the reconfigured BWP or BWPs and a CAconfiguration in use by the UE. In some embodiments, the UE maydetermine a DC location of the UE's transmitter and a DC location of theUE's receiver.

At step 930, the UE may transmit a DC location report to the BS. The DClocation report may indicate the DC location determined for thereconfigured BWP or BWPs.

At step 940, the BS determines PTRS configurations based on the DClocation report. For example, the BS may configure UL and/or DLresources for PTRS transmissions avoiding DC tones indicated in thereceived DC location report.

At step 950, the BS transmits PTRS configurations to the UE.

At step 960, the BS transmits PTRSs using the configured DL resources tofacilitate phase tracking at the UE. For example, the PTRSs are includedin DL signals carrying DL data.

At step 970, the UE transmits PTRSs using the configured UL resources tofacilitate phase tracking at the BS. For example, the PTRSs are includedin UL signals carrying UL data.

In an embodiment, to avoid a large amount of UL DC location reportsignaling, a network may signal a limited potential combinations ofactive BWPs across all configured CCs. As such, the UE can signal the DClocations for the potential active BWP combinations.

In an embodiment, a BS (e.g., the BSs 105 and 600) may configure a setof reference BWPs. The configuration for the set of reference BWPs canbe performed at the RRC layer for a particular UE. The set of referenceBWPs can be within a single CC or across multiple CCs. In someembodiments, the set of reference BWPs can be a subset of configuredBWPs of the UE. The UE may determine DC locations for the set ofreference BWPs. In some embodiments, the UE may transmit a DC locationreport including a band report indicating a set of DC locations as afunction of band combinations.

FIG. 10 illustrates a DC location reporting method 1000 according tosome embodiments of the present disclosure. The method can be employedby the network 100. In particular, the method 1000 can be implemented bya UE such as the UEs 115 and 500 for DC location reporting. In FIG. 10 ,the y-axis represents frequency in some constant units. The method 1000can be used in conjunction with the methods 700, 800, and 900 describedabove with respect to FIGS. 7, 8, and 9 , respectively. As an example,an RF chain of the UE may receive three intra-band CCs 1010, 1020, and1030 (e.g., the CCs 210 and 220). The UE may use a single localoscillator to down-convert a received RF signal to a baseband signalwith a DC frequency 1002. As shown, the DC frequency 1002 is mapped to asubcarrier 1042 indexed 6 within a resource block (RB) 1040 where the DCfrequency 1002 resides. The UE may report the subcarrier index 6 withinthe RB 1040 to a BS (e.g., the BSs 105 and 600). For example, the UE mayreport a subcarrier index offset value to the BS. The DC location reportmessage is described in greater detail herein below with respect to FIG.11 . Upon receiving the report, the BS may configure the UE with a PTRSthat does not overlap with the subcarrier indexed 6 to avoid collisionbetween the PTRS and the DC tone.

While the method 1000 is described in the context of reporting a DClocation of the UE's receiver, the method 1000 can be applied to reporta DC location of the UE's transmitter. For example, the DC location ofthe UEs transmitter may be based on the UE's baseband and up-conversionhardware implementation.

FIG. 11 illustrates a DC location report message element 1100 accordingto some embodiments of the present disclosure. The message element 1100can be used by a UE such as the UEs 115 and 500 to report DC locationinformation. As described above in the method 1000, a UE may report asubcarrier offset within an RB to indicate a DC location (e.g., the DCfrequency 1002). In an embodiment, the message element 1100 may have alength of 4 bits (e.g., shown as b0, b1, b2, and b3). The messageelement 1100 can have values varying between 0 and 15.

For example, when the message element 1100 includes a value between 0and 11, the value indicates a DC subcarrier index within an RB (e.g.,the RB 1040) where the DC frequency resides. A value of 12 in themessage element 1100 may indicate a don't care condition, where the DCtone may be outside of the band of interest or the UE may apply analgorithm with a strong DC rejection. A value of 13 in the messageelement 1100 may indicate a nondeterministic condition, where the DCtone may reside within an RB (e.g., the RB 1040), but the mapping of theDC tone to the subcarrier index may not be specified. This maycorrespond to the scenario when UE uses fast frequency hopping and thusthe DC location changes rapidly. Remaining values of 14 and 15 may bereserved for future use.

The UE may transmit the message element 1100 via a physical uplinkcontrol channel (PUCCH) signaling or RRC signaling. The UE may provideDC location information to the BS using any suitable signalingconfiguration, which may be dependent on the implementation and/orapplication of the UE. For example, the UE may transmit a messageelement 1100 for each CC and/or each BWP. Alternatively, the UE maytransmit a message element 1100 for a set of intra-band CCs (e.g., theCCs 1010, 1020, and 1030) in a CA scenario. Yet alternatively, the UEmay transmit a message element 1100 for an entire band. For the scenariodescribed in the method 1000, the UE may report a subcarrier index of 6for DC location reporting.

In some embodiments, the UE may transmit two message elements 1100(e.g., a total of 8 bits), one indicating a DC location of the UE'stransmitter and another indicating a DC location of the UE's receiver.While the message element 1100 is illustrated with a bit-length of 4,the message element 1100 can be alternatively configured to include adifferent bit-length (e.g., 5, 8, or more) to achieve similarfunctionalities. The bit-length of 4 may be configured to support thereporting of a subcarrier offset in an RB (e.g., the RB 1040) havingabout twelve subcarriers (e.g., the subcarriers indexed 0-11 in FIG. 10) and to provide an additional don't care condition.

In some embodiments, the UE may include a BWP index or a CC index witheach message element 1100. For example, the UE may report four DClocations for four BWPs by including a BWP index and a message element1100 for each BWP in a report. Alternatively, the UE may report eight DClocations for eight CCs by including a CC index and a message element1100 for each CC in a report.

In some other embodiments, a UE may report a DC location of the UE usingan absolute radio frequency channel number (ARFCN) instead of using themessage element 1100. For example, the UE may include an ARFCN for eachcorresponding BWP or each CC in a report.

In some other embodiments, a UE may have a DC frequency tone locatedbetween two adjacent subcarriers, where the DC tone may equally orcomparably impact or interfere with both subcarriers. In suchembodiments, the message element 1100 may be extended to include alength of about 5 bits with values varying between 0 and 31. Forexample, values between 0 and 13 may represent the same DC informationas descried above. Other values, for example, between 14 and 25, mayindicate that a DC location is between two adjacent subcarriers. Forexample, a value of 14 may indicate that the DC location is betweensubcarriers of indices 0 and 1. Similarly, a value of 15 may indicatethat the DC location is between subcarriers of indices 1 and 2, and soon. Similarly or alternatively, a value of 25 may indicate that the DClocation is between the subcarrier of index 11 in an RB and thesubcarrier of index 0 in the next RB (e.g., the DC tone resides on theboundaries of two adjacent RBs). Remaining values of 26 to 31 may bereserved for future use. In some other embodiments, the values in themessage elements 1100 may be alternatively configured to achieve similarfunctionalities.

FIG. 12 illustrates a PTRS RE-level offset configuration 1200 accordingto some embodiments of the present disclosure. The configuration 1200may be employed by a network such as the network 100. In particular, aBS such as the BSs 105 and 600 may use the configuration 1200 toconfigure PTRSs based on DC location reports received from UEs such asthe UEs 115 and 500. As shown, a PTRS configuration may be associatedwith a demodulation reference signal (DMRS) port configuration. EachDMRS port configuration refers to the mapping of a DMRS to physical REsor subcarriers for a particular antenna port. In addition, differenttypes of DMRSs may have different DMRS port configurations.

In FIG. 12 , the column 1210 shows PTRS-RE-offset configurationsrepresented by binary values 00, 01, 10, and 11. The columns 1220, 1230,1240, and 1250 show the subcarrier indices or offsets (e.g., in adecimal format) of a subcarrier or RE configured or mapped for PTRStransmissions associated with DMRS port numbers represented by 1000,1001, 1002, and 1003, respectively, when up to 4 DMRS ports areconfigured. As an example, when the PTRS-RE-offset configuration is 01and the associated DMRS port number is 1001, a PTRS may be transmittedusing a resource element (RE) or a subcarrier at a subcarrier offset of4 (e.g., at every symbol of a data signal) as shown by the dashed circle1202. The PTRS-RE-offset configuration 1200 may be similar to thePTRS-RE-offset configuration defined in the 3GPP document TS 38.211version 15.1.0, Apr. 3, 2018.

In some embodiments, a BS may determine a PTRS-RE-offset configurationfor UL PTRSs and a PTRS-RE-offset configuration for DL PTRSs. Inaddition, a BS may determine a PTRS-RE-offset configuration based on aDMRS configuration type. For example, NR may support a DMRSconfiguration type 1 and a DMRS configuration type 2. Thus, a BS maydetermine a UL PTRS-RE-offset configuration and a DL PTRS-RE-offsetconfiguration for DL PTRSs for DMRS configuration type 1 and a ULPTRS-RE-offset configuration and a DL PTRS-RE-offset configuration forDL PTRSs for DMRS configuration type 2.

In some embodiments, the use of DMRS configuration type 1 or DMRSconfiguration type 2 may depend on a UE-specific configuration. Forexample, DMRS configuration type 1 may support up to about 4 ports,while DMRS configuration type 2 may support up to about 6 ports (in thecase of one DMRS symbol configuration). In addition, DMRS configurationtype 1 may have a higher DMRS tone density than DMRS configuration type2. Thus, DMRS configuration type 1 may allow for improved channelestimation performance. As such, DMRS configuration type 1 may be usedfor transmissions where low-rank, high-reliability is of importance,e.g., broadcast information. Conversely, DMRS configuration type 2 maybe used for transmissions where high-rank, high data rate is ofimportance.

For the scenario described in the method 1000, where the UE's receiverDC tone overlaps with the subcarrier indexed 6, the BS may not configurethe UE with a DL-PTRS-RE-offset of 10 (e.g., with subcarrier indexed 6as shown by the dashed circle 1204) to avoid collision between a DL PTRSand the DC tone of the UE's receiver. Similarly, when a DC locationreport in the method 1000 includes a DC tone of the UE's transmitter,the BS may not configure the UE with a UL-PTRS-RE-offset of 10 to avoidcollisions between a UL PTRS and a DC tone of the UE's transmitter. Inan embodiment, a BS may not require the absolute frequency of the DClocation for the determination of a DL-PTRS-RE-offset and/or aUL-PTRS-RE-offset.

In another example, a UE's receiver may include a DC frequency betweenthe subcarriers indexed 5 and 6. For instances, the DC frequency maygenerate a peak signal at the UE's receiver causing interference to thesubcarriers indexed 5 and 6. Thus, the BS may not configure the UE witha DL-PTRS-RE-offset of 01 or 10 to avoid collision between a DL PTRS andthe DC peak signal at the subcarriers indexed 5 and 6.

FIG. 13 illustrates a DC location report message element 1300 accordingto some embodiments of the present disclosure. The message element 1300can be used by a UE such as the UEs 115 and 500 to report DC locationinformation. As described above in the method 1000, a UE may report asubcarrier offset within an RB to indicate a DC location (e.g., the DCfrequency 1002). In an embodiment, the message element 1300 may have alength of 4 bits (e.g., shown as b0, b1, b2, and b3). The messageelement 1300 may include a field 1310 and a field 1320. The field 1310may be about 2 bits in length and may indicate a PTRS-RE-offsetconfiguration for DMRS configuration type 1. The field 1320 may be about2 bits in length and may indicate a PTRS-RE-offset configuration forDMRS configuration type 2. The PTRS-RE-offset configuration in the field1310 or the field 1320 may correspond to values in the column 1210 ofthe configuration 1200. In other words, instead of having a UE to reportthe subcarrier location of a DC frequency of the UE's transmitter or theUE's receiver, the UE may select a PTRS-RE-offset configuration that theBS may use and report the PTRS-RE-offset configuration to the BSdirectly. Subsequently, the BS may configure PTRSs based on thePTRS-RE-offset configuration selected by the UE.

In some embodiments, the UE may transmit two message elements 1300, oneindicating a PTRS-RE-offset configuration for UL and another indicatinga PTRS-RE-offset configuration for DL. While the message element 1300 isillustrated with a bit-length of 4, the message element 1300 can bealternative configured to include a different bit-length (e.g., 6, 8, ormore) to achieve similar functionalities when the number DMRS portconfigurations increases or the number of DMRS types increases.

FIG. 14 is a flow diagram of a DC location reporting and PTRScommunication method 1400 according to embodiments of the presentdisclosure. Steps of the method 1400 can be executed by a computingdevice (e.g., a processor, processing circuit, and/or other suitablecomponent) of a wireless communication device or other suitable meansfor performing the steps. For example, a wireless communication device,such as the UE 115 or UE 500, may utilize one or more components, suchas the processor 502, the memory 504, the DC location reporting module508, the transceiver 510, the modem 512, and the one or more antennas516, to execute the steps of method 1400. Additionally or alternatively,and in particular, processor 502 may be configured to perform step 1420and transceiver 510 may be configured to perform steps 1410, 1430,and/or optional step 1440. The method 1400 may employ similar mechanismsas in the methods 700, 800, 900, and 1000 described above with respectto FIGS. 7, 8, 9, and 10 , respectively. As illustrated, the method 1400includes a number of enumerated steps, but embodiments of the method1400 may include additional steps before, after, and in between theenumerated steps. In some embodiments, one or more of the enumeratedsteps may be omitted or performed in a different order.

At step 1410, the method 1400 includes receiving, by a wirelesscommunication device from a base station (e.g., the BSs 105 and 600), atleast one of CA configuration or a BWP configuration. In some instances,the CA configuration may be a CA reconfiguration and the BWPconfiguration may be associated with a BWP reconfiguration or an activeBWP switch.

At step 1420, the method 1400 includes determining, by the wirelesscommunication device, a DC location (e.g., the DC locations 202, 204,206, and 1002) based on at least one of the CA configuration or the BWPconfiguration.

At step 1430, the method 1400 includes transmitting, by the wirelesscommunication device to the base station, a report based on thedetermined DC location.

At step 1440, the method 1400 optionally includes communicating, by thewireless communication device with the base station, a phase trackingreference signal (PTRS) configured based on the report.

In an embodiment, the report may include subcarrier offset informationof one or more subcarriers overlapping with a DC location of thewireless communication device. For example, the subcarrier offsetinformation may indicate subcarrier index 6 for the method 1000described above. Alternatively, the subcarrier offset information mayindicate that the DC location is between two adjacent subcarriers. Thereport may include a message element similar to the message element1100. Alternatively, the report may indicate the location of an RBincluding the DC location. In such an embodiment, the wirelesscommunication device may receive an RE mapping (e.g., the PTRS-RE-offsetconfigurations in the column 1210 of FIG. 12 ) from the BS forcommunicating the PTRS.

In an embodiment, the wireless communication device may determine an REmapping for communicating the PTRS based on the determined DC locationand may include the RE mapping in the report. For example, the reportmay include a message element similar to the message element 1300.

In an embodiment, the DC location may correspond to the DC location of atransmitter of the wireless communication device. In such an embodiment,communicating, by the wireless communication device with the basestation, the PTRS can include transmitting the PTRS to the base station.

In an embodiment, the DC location may correspond to the DC location of areceiver of the wireless communication device. In such an embodiment,communicating, by the wireless communication device with the basestation, the PTRS can include receiving the PTRS from the base station.

FIG. 15 is a flow diagram of a PTRS communication method 1500 accordingto embodiments of the present disclosure. Steps of the method 1500 canbe executed by a computing device (e.g., a processor, processingcircuit, and/or other suitable component) of a wireless communicationdevice or other suitable means for performing the steps. For example, awireless communication device, such as the BS 105 or BS 600, may utilizeone or more components, such as the processor 602, the memory 604, thePTRS configuration module 608, the transceiver 610, and the one or moreantennas 616, to execute the steps of method 1500. Additionally oralternatively, and in particular, processor 602 may be configured toperform step 1530 and transceiver 610 may be configured to perform steps1510, 1520, and/or optional step 1540. The method 1500 may employsimilar mechanisms as in the methods 700, 800, 900, and 1000 and theconfiguration 1200 described above with respect to FIGS. 7, 8, 9, 10,and 12 , respectively. As illustrated, the method 1500 includes a numberof enumerated steps, but embodiments of the method 1500 may includeadditional steps before, after, and in between the enumerated steps. Insome embodiments, one or more of the enumerated steps may be omitted orperformed in a different order.

At step 1510, the method 1500 includes transmitting, by a BS to awireless communication device (e.g., the UEs 115 and 500), at least oneof a CA configuration or a BWP configuration. In some instances, the CAconfiguration may be a CA reconfiguration and the BWP configuration maybe associated with a BWP reconfiguration or an active BWP switch.

At step 1520, the method 1500 includes receiving, by the BS from thewireless communication device, a report indicating DC locationinformation associated with the wireless communication device inresponse to at least one of the CA configuration or the BWPconfiguration.

At step 1530, the method 1500 includes determining, by the BS, a PTRSconfiguration (e.g., an RE mapping similar to the PTRS-RE-offsetconfigurations in the column 1210 of FIG. 12 ) based on the DC locationinformation in the report.

At step 1540, the method 1500 optionally includes communicating, by theBS with the wireless communication device, a PTRS based on thedetermined PTRS configuration.

In an embodiment, the report may include subcarrier offset informationof one or more subcarriers overlapping with a DC location of thewireless communication device. For example, the subcarrier offsetinformation may indicate subcarrier index 6 for the method 1000described above. Alternatively, the subcarrier offset information mayindicate that the DC location is between two adjacent subcarriers. Thereport may include a message element similar to the message element1100. Alternatively, the report may include an RB including a DClocation of the wireless communication device. In an embodiment, thereport may include an RE mapping for communicating the PTRS. Forexample, the report may include a message element similar to the messageelement 1300. In an embodiment, the BS may determine the PTRSconfiguration by configuring UL and/or DL resources for UL and/or PTRStransmissions to avoid using subcarriers that overlap with the DClocation of the wireless communication device.

In an embodiment, the DC location may correspond to the DC location of atransmitter of the wireless communication device. In such an embodiment,communicating, by the BS with the wireless communication device, thePTRS can include receiving the PTRS from the BS based on the DC locationinformation in the report.

In an embodiment, the DC location may correspond to the DC location of areceiver of the wireless communication device. In such an embodiment,communicating, by the BS with the wireless communication device, thePTRS can include transmitting the PTRS to the BS based on the DClocation information in the report.

In an embodiment, for UL, DC location signaling is included in anRRCReconfigurationComplete message. A UE reports a DC location perconfigured BWP and per serving cell upon a BWP configuration and aserving cell configuration. A UE may send an RRCReconfigurationCompletemessage to a BS to confirm the successful completion of an RRCconnection reconfiguration. The RRCReconfigurationComplete messageincludes an uplinkTxDirectCurrentList information element (IE). TheuplinkTxDirectCurrentList IE indicates the Tx Direct Current locationsper serving cell for each configured UL BWP in the serving cell based onthe BWP numerology and the associated carrier bandwidth. TheUplinkTxDirectCurrentList IE includes a sequence ofUplinkTxDirectCurrentCell fields as shown below:

-   -   UplinkTxDirectCurrentList::=SEQUENCE (SIZE (1 . . .        maxNrofServingCells)) OF UplinkTxDirectCurrentCell

Each UplinkTxDirectCurrentCell field includes a sequence of tuples eachincluding a servCellIndex field and a uplinkDirectCurrentBWP field asshown below:

UplinkTxDirectCurrentCell ::= SEQUENCE {  servCellIndexServCellIndex,(config serving cell, 0 = pcell, 1 = scell uplinkDirectCurrentBWP SEQUENCE (SIZE (1..maxNrofBWPs)) OFUplinkTxDirectCurrentBWP,  ... }.

The servCellIndex field indicates a serving cell ID of the serving cellcorresponding to the uplinkDCLocationsPerBWP. For instance, theservCellIndex field may be set to a value of 0 to indicate a primarycell (PCell), a value of 1 to indicate a first secondary cell (SCell),or a value of 2 to indicate a second SCell. The uplinkDirectCurrentBWPfield indicates Tx Direct Current locations for all the uplink BWPsconfigured at the corresponding serving cell.

The uplinkDirectCurrentBWP field includes a sequence of tuples eachincluding a bwp-Id field, a shift7dot5 kHz field, and atxDirectCurrentLocation field as shown below:

UplinkTxDirectCurrentBWP ::= SEQUENCE {  bwp-Id BWP-Id,(4 BWPs) shift7dot5kHz BOOLEAN,  txDirectCurrentLocation INTEGER (0..3301) }.The bwp-Id field indicates the BWP-Id of the corresponding uplink BWP.The shift7dot5 kHz field indicates whether there is 7.5 kHz shift ornot. A 7.5 kHz shift is applied if the field is set to TRUE. The 7.5 kHzshift may be applied, for example, to the txDirectCurrentLocationrepresenting a subcarrier distance from a reference point. Hence, a 7.5kHz shift may be applied, for example 7.5 kHz may be added, to thefrequency value of the subcarrier indicated by the subcarrier indexindicated by txDirectCurrentLocation. The new DC location may beindicated by the resulting value after the shift is applied (ifindicated by shift7dot5 kHz). Otherwise 7.5 kHz shift is not applied.The txDirectCurrentLocation field indicates the uplink Tx Direct Currentlocation for the carrier. The txDirectCurrentLocation field is set to avalue in the value range between 0 and 3299 to indicate the subcarrierindex within the carrier corresponding to the numerology of thecorresponding uplink BWP, a value of 3300 to indicate “Outside thecarrier”, and a value of 3301 to indicate “Undetermined position withinthe carrier”. For instance, each UE may be configured with up to aboutfour BWPs for each CC. As such, a UE may report up to about fourUplinkTxDirectCurrentBWP fields for each CC, where eachUplinkTxDirectCurrentBWP field may correspond to one BWP for a given CC.

Accordingly, in some instances, a UE may include a band report includingDC locations as a function of configured bands or BWPs (e.g., the fourBWPs) using the UplinkTxDirectCurrentList IE. For example, the DClocation reports in the methods 700, 800, 900, 1400, and/or 1500described above with respect to FIGS. 7, 8, 9, 14 , and/or 15,respectively, may indicate DC locations using theUplinkTxDirectCurrentList IE. Further, in some instances, the UE maytransmit a DC location report by transmitting anRRCReconfigurationComplete message based upon a BWP configuration, a BWPswitch, a BWP reconfiguration, and/or a serving cell configuration.

Information and signals may be represented using any of a variety ofdifferent technologies and techniques. For example, data, instructions,commands, information, signals, bits, symbols, and chips that may bereferenced throughout the above description may be represented byvoltages, currents, electromagnetic waves, magnetic fields or particles,optical fields or particles, or any combination thereof.

The various illustrative blocks and modules described in connection withthe disclosure herein may be implemented or performed with ageneral-purpose processor, a DSP, an ASIC, an FPGA or other programmablelogic device, discrete gate or transistor logic, discrete hardwarecomponents, or any combination thereof designed to perform the functionsdescribed herein. A general-purpose processor may be a microprocessor,but in the alternative, the processor may be any conventional processor,controller, microcontroller, or state machine. A processor may also beimplemented as a combination of computing devices (e.g., a combinationof a DSP and a microprocessor, multiple microprocessors, one or moremicroprocessors in conjunction with a DSP core, or any other suchconfiguration).

The functions described herein may be implemented in hardware, softwareexecuted by a processor, firmware, or any combination thereof. Ifimplemented in software executed by a processor, the functions may bestored on or transmitted over as one or more instructions or code on acomputer-readable medium. Other examples and implementations are withinthe scope of the disclosure and appended claims. For example, due to thenature of software, functions described above can be implemented usingsoftware executed by a processor, hardware, firmware, hardwiring, orcombinations of any of these. Features implementing functions may alsobe physically located at various positions, including being distributedsuch that portions of functions are implemented at different physicallocations. Also, as used herein, including in the claims, “or” as usedin a list of items (for example, a list of items prefaced by a phrasesuch as “at least one of or” “one or more of”) indicates an inclusivelist such that, for example, a list of [at least one of A, B, or C]means A or B or C or AB or AC or BC or ABC (i.e., A and B and C).

As those of some skill in this art will by now appreciate and dependingon the particular application at hand, many modifications, substitutionsand variations can be made in and to the materials, apparatus,configurations and methods of use of the devices of the presentdisclosure without departing from the spirit and scope thereof. In lightof this, the scope of the present disclosure should not be limited tothat of the particular embodiments illustrated and described herein, asthey are merely by way of some examples thereof, but rather, should befully commensurate with that of the claims appended hereafter and theirfunctional equivalents.

What is claimed is:
 1. A method of wireless communication, comprising:receiving, by a wireless communication device, a carrier aggregation(CA) configuration configuring the wireless communication device for CAwith a plurality of component carriers (CCs); determining, by thewireless communication device based on the CA configuration, a singledirect current (DC) location for a set of bandwidth parts (BWPs)associated with the plurality of CCs; and transmitting, by the wirelesscommunication device, a report including an indication of the single DClocation for the plurality of CCs.
 2. The method of claim 1, the reportfurther including one or more BWP indices identifying the set of BWPs.3. The method of claim 1, further comprising: receiving, by the wirelesscommunication device, a BWP configuration configuring the wirelesscommunication device with the set of BWPs.
 4. The method of claim 1,wherein the determining includes determining a resource block (RB) thatincludes the single DC location for a BWP of the set of BWPs, andwherein the transmitting includes transmitting the report includinginformation associated with the determined RB.
 5. The method of claim 1,wherein the determining includes determining one or more subcarriersoverlapping with the single DC location for a BWP of the set of BWPs,and wherein the transmitting includes transmitting the report includingsubcarrier offset information of the determined one or more subcarriers.6. The method of claim 1, further comprising: communicating, by thewireless communication device with a network entity, a phase trackingreference signal (PTRS) configured based on the report.
 7. The method ofclaim 6, further comprising: receiving, by the wireless communicationdevice from the network entity in response to the report, a resourceelement (RE) mapping for communicating the PTRS.
 8. The method of claim6, further comprising: determining, by the wireless communicationdevice, a resource element (RE) mapping for communicating the PTRS basedon the single DC location, wherein the transmitting includestransmitting the report including the determined RE mapping.
 9. Themethod of claim 6, wherein the single DC location is associated with atransmitter of the wireless communication device, and wherein thecommunicating includes: transmitting, by the wireless communicationdevice to the network entity, the PTRS.
 10. The method of claim 6,wherein the single DC location is associated with a receiver of thewireless communication device, and wherein the communicating includes:receiving, by the wireless communication device from the network entity,the PTRS.
 11. The method of claim 1, wherein the plurality of CCs areintra-band CCs.
 12. A first wireless communication device, comprising: amemory; a transceiver; and a processor in communication with the memoryand the transceiver, wherein the first wireless communication device isconfigured to: receive, via the transceiver, a carrier aggregation (CA)configuration configuring the wireless communication device for CA witha plurality of component carriers (CCs); determine, based on the CAconfiguration, a single direct current (DC) location for a set ofbandwidth parts (BWPs) associated with the plurality of CCs; andtransmit, via the transceiver, a report including an indication of thesingle DC location for the plurality of CCs.
 13. The first wirelesscommunication device of claim 12, the report further including a BWPindex identifying the set of BWPs.
 14. The first wireless communicationdevice of claim 12, wherein the first wireless communication device isfurther configured to: receive, via the transceiver, a BWP configurationconfiguring the wireless communication device with the set of BWPs. 15.The first wireless communication device of claim 12, wherein the firstwireless communication device configured to determine the single DClocation comprises the first wireless communication device configured todetermine a resource block (RB) that includes the single DC location fora BWP of the set of BWPs, and wherein the first wireless communicationdevice configured to transmit the report comprises the first wirelesscommunication device configured to transmit the report includinginformation associated with the determined RB.
 16. The first wirelesscommunication device of claim 12, the first wireless communicationdevice configured to determine the single DC location comprises thefirst wireless communication device configured to determine one or moresubcarriers overlapping with the single DC location for a BWP of the setof BWPs, and the first wireless communication device configured totransmit the report comprises the first wireless communication deviceconfigured to transmit the report including subcarrier offsetinformation of the determined one or more subcarriers.
 17. The firstwireless communication device of claim 12, wherein the first wirelesscommunication device is further configured to: communicate, with anetwork entity via the transceiver, a phase tracking reference signal(PTRS) configured based on the report.
 18. The first wirelesscommunication device of claim 17, wherein the first wirelesscommunication device is further configured to: receive, via thetransceiver from the network entity in response to the report, aresource element (RE) mapping for communicating the PTRS.
 19. The firstwireless communication device of claim 17, wherein the first wirelesscommunication device is further configured to: determine a resourceelement (RE) mapping for communicating the PTRS based on the single DClocation, wherein the first wireless communication device configured totransmit the report comprises the first wireless communication deviceconfigured to transmit the report including the determined RE mapping.20. The first wireless communication device of claim 17, wherein thesingle DC location is associated with a transmitter of the wirelesscommunication device, and wherein the first wireless communicationdevice configured to communicate the PTRS comprises: the first wirelesscommunication device configured to transmit, via the transceiver to thenetwork entity, the PTRS.
 21. The first wireless communication device ofclaim 17, wherein the single DC location is associated with a receiverof the wireless communication device, and wherein the first wirelesscommunication device configured to communicate the PTRS comprises: thefirst wireless communication device configured to receive, via thetransceiver from the network entity, the PTRS.
 22. The first wirelesscommunication device of claim 12, wherein the plurality of CCs areintra-band CCs.
 23. A non-transitory, computer-readable medium havingprogram code recorded thereon, wherein the program code comprisesinstructions executable by a processor of a first wireless communicationdevice to cause the first wireless communication device to: receive acarrier aggregation (CA) configuration configuring the wirelesscommunication device for CA with a plurality of component carriers(CCs); determine, based on the CA configuration, a single direct current(DC) location for a set of bandwidth parts (BWPs) associated with theplurality of CCs; and transmit a report including an indication of thesingle DC location for the plurality of CCs.
 24. The non-transitory,computer-readable medium of claim 23, the report further including a BWPindex identifying the set of BWPs.
 25. A first wireless communicationdevice, comprising: means for receiving a carrier aggregation (CA)configuration configuring the wireless communication device for CA witha plurality of component carriers (CCs); means for determining, based onthe CA configuration, a single direct current (DC) location for a set ofbandwidth parts (BWPs) associated with the plurality of CCs; and meansfor transmitting a report including an indication of the single DClocation for the plurality of CCs.
 26. The first wireless communicationdevice of claim 25, the report further including a BWP index identifyingthe set of BWPs.